Water and oil repellent composition

Abstract

A water and oil repellent composition having excellent durability, which can impart excellent water and oil repellency to an object, even in a process at low temperatures, and which enables water and oil repellent treatment providing a soft hand. A water and oil repellent composition which comprises, as an essential component, a copolymer containing polymerization units of the following monomer (a) and polymerization units of the following monomer (b): monomer (a): an R f group-containing monomer which forms a photopolymer having no melting point or a melting point of at most 55° C. attributable to fine crystals derived from the R f groups and having a glass transition point of at least 20° C. monomer (b): a monomer having no R f group and having a cross-linkable functional group.

1 . A water and oil repellent composition, which comprises, as an essential component, a copolymer containing at least 80 mass % of polymerization units of the following monomer (a) and polymerization units of the following monomer (b): 
 Monomer (a): a monomer having a polyfluoroalkyl group, which forms a homopolymer having no melting point or a melting point of at most 55° C. attributable to fine crystals derived from the polyfluoroalkyl group, and having a glass transition point of at least 20° C.,    Monomer (b): a monomer having no polyfluoroalkyl group and having a cross-linkable functional group.    
   
   
       2 . The water and oil repellent composition according to  claim 1 , wherein the copolymer is a copolymer containing polymerization units of the following monomer (c): 
 Monomer (c): at least one monomer having no polyfluoroalkyl group other than the monomer (b), which contains at least 50 mass % of the following monomer (c1) or the following monomer (c2), based on the total amount of the monomer (c),    Monomer (c1): a monomer which forms a homopolymer having a melting point of at least 30° C. attributable to fine crystals,    Monomer (c2): a monomer other than the monomer (c1), which forms a homopolymer having a glass transition point of from −50° C. to 40° C.    
   
   
       3 . A water and oil repellent composition, which comprises, as an essential component, a copolymer containing at least 30 mass % and less than 80 mass % of polymerization units of the following monomer (a) and polymerization units of the following monomer (b), and further containing polymerization units of the following monomer (c): 
 Monomer (a): a monomer having a polyfluoroalkyl group, which forms a homopolymer having no melting point or a melting point of at most 55° C. attributable to fine crystals derived from the polyfluoroalkyl group, and further, having a glass transition point of least 20° C.,    Monomer (b): A monomer having no polyfluoroalkyl group and having a cross-linkable functional group;    Monomer (c): at least one monomer having no polyfluoroalkyl group other than the monomer (b), which contains at least 50 mass % of the following monomer (c1) or the following monomer (c2), based on the total amount of the monomer (c),    Monomer (c1): a monomer which forms a homopolymer having a melting point of at least 30° C. attributable to fine crystals,    Monomer (c2): a monomer other than the monomer (c1), which forms a homopolymer having a glass transition point of from −50° C. to 40° C.    
   
   
       4 . The water and oil repellent composition according to  claim 1 , wherein the monomer (a) is a compound represented by (Z-Y) n X provided that the symbols in the formula have the following meanings: 
 Z: a perfluoroalkyl group having at most 6 carbon atoms,    Y: a bivalent organic group or a single bond,    n: 1 or 2,    X: a polymerizable unsaturated group, which is —CR═CH 2 , —COOCR═CH 2 , —OCOCR═CH 2 , —OCH 2 -φ-CR═CH 2  or —OCH═CH 2  when n is 1, and is ═CH(CH 2 ) m CR═CH 2 , ═CH(CH 2 ) m COOCR═CH 2 , ═CH(CH 2 ) m OCOCR═CH 2  or —OCOCH═CHCOO— when n is 2, wherein R is a hydrogen atom, a methyl group or a halogen atom, φ is a phenylene group and m is an integer of from 0 to 4.    
   
   
       5 . The water and oil repellent composition according to  claim 1 , wherein the water and oil repellent composition contains at least one medium selected from the group consisting of water, an alcohol, a glycol, a glycol ether and a glycol ester.